diff mbox

[v2] spi/bfin_sport_spi: new driver for a SPI bus via the Blackfin SPORT peripheral

Message ID 1294773725-4026-1-git-send-email-vapier@gentoo.org (mailing list archive)
State Superseded, archived
Headers show

Commit Message

Mike Frysinger Jan. 11, 2011, 7:22 p.m. UTC
None
diff mbox

Patch

diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
index 1906840..95ba5fe 100644
--- a/drivers/spi/Kconfig
+++ b/drivers/spi/Kconfig
@@ -66,6 +66,15 @@  config SPI_BFIN
 	help
 	  This is the SPI controller master driver for Blackfin 5xx processor.
 
+config SPI_BFIN_SPORT
+	tristate "SPI bus via Blackfin SPORT"
+	depends on BLACKFIN
+	help
+	  Enable support for a SPI bus via the Blackfin SPORT peripheral.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called bfin_sport_spi.
+
 config SPI_AU1550
 	tristate "Au1550/Au12x0 SPI Controller"
 	depends on (SOC_AU1550 || SOC_AU1200) && EXPERIMENTAL
diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
index 3a42463..d937ebf 100644
--- a/drivers/spi/Makefile
+++ b/drivers/spi/Makefile
@@ -11,6 +11,7 @@  obj-$(CONFIG_SPI_MASTER)		+= spi.o
 # SPI master controller drivers (bus)
 obj-$(CONFIG_SPI_ATMEL)			+= atmel_spi.o
 obj-$(CONFIG_SPI_BFIN)			+= spi_bfin5xx.o
+obj-$(CONFIG_SPI_BFIN_SPORT)		+= bfin_sport_spi.o
 obj-$(CONFIG_SPI_BITBANG)		+= spi_bitbang.o
 obj-$(CONFIG_SPI_AU1550)		+= au1550_spi.o
 obj-$(CONFIG_SPI_BUTTERFLY)		+= spi_butterfly.o
diff --git a/drivers/spi/bfin_sport_spi.c b/drivers/spi/bfin_sport_spi.c
new file mode 100644
index 0000000..d814e12
--- /dev/null
+++ b/drivers/spi/bfin_sport_spi.c
@@ -0,0 +1,949 @@ 
+/*
+ * SPI bus via the Blackfin SPORT peripheral
+ *
+ * Enter bugs at http://blackfin.uclinux.org/
+ *
+ * Copyright 2009 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/spi/spi.h>
+#include <linux/workqueue.h>
+
+#include <asm/portmux.h>
+#include <asm/bfin5xx_spi.h>
+#include <asm/blackfin.h>
+#include <asm/bfin_sport.h>
+#include <asm/cacheflush.h>
+
+#define DRV_NAME	"bfin-sport-spi"
+#define DRV_DESC	"SPI bus via the Blackfin SPORT"
+
+MODULE_AUTHOR("Cliff Cai");
+MODULE_DESCRIPTION(DRV_DESC);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:bfin-sport-spi");
+
+enum bfin_sport_spi_state {
+	START_STATE,
+	RUNNING_STATE,
+	DONE_STATE,
+	ERROR_STATE,
+};
+
+struct bfin_sport_spi_master_data;
+
+struct transfer_ops {
+	void (*write) (struct bfin_sport_spi_master_data *);
+	void (*read) (struct bfin_sport_spi_master_data *);
+	void (*duplex) (struct bfin_sport_spi_master_data *);
+};
+
+struct bfin_sport_spi_master_data {
+	/* Driver model hookup */
+	struct device *dev;
+
+	/* SPI framework hookup */
+	struct spi_master *master;
+
+	/* Regs base of SPI controller */
+	struct sport_register __iomem *regs;
+	int err_irq;
+
+	/* Pin request list */
+	u16 *pin_req;
+
+	/* Driver message queue */
+	struct workqueue_struct *workqueue;
+	struct work_struct pump_messages;
+	spinlock_t lock;
+	struct list_head queue;
+	int busy;
+	bool run;
+
+	/* Message Transfer pump */
+	struct tasklet_struct pump_transfers;
+
+	/* Current message transfer state info */
+	enum bfin_sport_spi_state state;
+	struct spi_message *cur_msg;
+	struct spi_transfer *cur_transfer;
+	struct bfin_sport_spi_slave_data *cur_chip;
+	union {
+		void *tx;
+		u8 *tx8;
+		u16 *tx16;
+	};
+	void *tx_end;
+	union {
+		void *rx;
+		u8 *rx8;
+		u16 *rx16;
+	};
+	void *rx_end;
+
+	int cs_change;
+	struct transfer_ops *ops;
+};
+
+struct bfin_sport_spi_slave_data {
+	u16 ctl_reg;
+	u16 baud;
+	u16 cs_chg_udelay;	/* Some devices require > 255usec delay */
+	u32 cs_gpio;
+	u16 idle_tx_val;
+	struct transfer_ops *ops;
+};
+
+static void
+bfin_sport_spi_enable(struct bfin_sport_spi_master_data *drv_data)
+{
+	bfin_write_or(&drv_data->regs->tcr1, TSPEN);
+	bfin_write_or(&drv_data->regs->rcr1, TSPEN);
+	SSYNC();
+}
+
+static void
+bfin_sport_spi_disable(struct bfin_sport_spi_master_data *drv_data)
+{
+	bfin_write_and(&drv_data->regs->tcr1, ~TSPEN);
+	bfin_write_and(&drv_data->regs->rcr1, ~TSPEN);
+	SSYNC();
+}
+
+/* Caculate the SPI_BAUD register value based on input HZ */
+static u16
+hz_to_spi_baud(u32 speed_hz)
+{
+	u_long clk, sclk = get_sclk();
+	int div = (sclk / (2 * speed_hz)) - 1;
+
+	if (div < 0)
+		div = 0;
+
+	clk = sclk / (2 * (div + 1));
+
+	if (clk > speed_hz)
+		div++;
+
+	return div;
+}
+
+/* Chip select operation functions for cs_change flag */
+static void
+bfin_sport_spi_cs_active(struct bfin_sport_spi_slave_data *chip)
+{
+	gpio_direction_output(chip->cs_gpio, 0);
+}
+
+static void
+bfin_sport_spi_cs_deactive(struct bfin_sport_spi_slave_data *chip)
+{
+	gpio_direction_output(chip->cs_gpio, 1);
+	/* Move delay here for consistency */
+	if (chip->cs_chg_udelay)
+		udelay(chip->cs_chg_udelay);
+}
+
+static void
+bfin_sport_spi_stat_poll_complete(struct bfin_sport_spi_master_data *drv_data)
+{
+	unsigned long timeout = jiffies + HZ;
+	while (!(bfin_read(&drv_data->regs->stat) & RXNE))
+		if (!time_before(jiffies, timeout))
+			break;
+		else
+			cpu_relax();
+}
+
+static void
+bfin_sport_spi_u8_writer(struct bfin_sport_spi_master_data *drv_data)
+{
+	u16 dummy;
+
+	while (drv_data->tx < drv_data->tx_end) {
+		bfin_write(&drv_data->regs->tx16, *drv_data->tx8++);
+		bfin_sport_spi_stat_poll_complete(drv_data);
+		dummy = bfin_read(&drv_data->regs->rx16);
+	}
+}
+
+static void
+bfin_sport_spi_u8_reader(struct bfin_sport_spi_master_data *drv_data)
+{
+	u16 tx_val = drv_data->cur_chip->idle_tx_val;
+
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tx16, tx_val);
+		bfin_sport_spi_stat_poll_complete(drv_data);
+		*drv_data->rx8++ = bfin_read(&drv_data->regs->rx16);
+	}
+}
+
+static void
+bfin_sport_spi_u8_duplex(struct bfin_sport_spi_master_data *drv_data)
+{
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tx16, *drv_data->tx8++);
+		bfin_sport_spi_stat_poll_complete(drv_data);
+		*drv_data->rx8++ = bfin_read(&drv_data->regs->rx16);
+	}
+}
+
+static struct transfer_ops bfin_transfer_ops_u8 = {
+	.write  = bfin_sport_spi_u8_writer,
+	.read   = bfin_sport_spi_u8_reader,
+	.duplex = bfin_sport_spi_u8_duplex,
+};
+
+static void
+bfin_sport_spi_u16_writer(struct bfin_sport_spi_master_data *drv_data)
+{
+	u16 dummy;
+
+	while (drv_data->tx < drv_data->tx_end) {
+		bfin_write(&drv_data->regs->tx16, *drv_data->tx16++);
+		bfin_sport_spi_stat_poll_complete(drv_data);
+		dummy = bfin_read(&drv_data->regs->rx16);
+	}
+}
+
+static void
+bfin_sport_spi_u16_reader(struct bfin_sport_spi_master_data *drv_data)
+{
+	u16 tx_val = drv_data->cur_chip->idle_tx_val;
+
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tx16, tx_val);
+		bfin_sport_spi_stat_poll_complete(drv_data);
+		*drv_data->rx16++ = bfin_read(&drv_data->regs->rx16);
+	}
+}
+
+static void
+bfin_sport_spi_u16_duplex(struct bfin_sport_spi_master_data *drv_data)
+{
+	while (drv_data->rx < drv_data->rx_end) {
+		bfin_write(&drv_data->regs->tx16, *drv_data->tx16++);
+		bfin_sport_spi_stat_poll_complete(drv_data);
+		*drv_data->rx16++ = bfin_read(&drv_data->regs->rx16);
+	}
+}
+
+static struct transfer_ops bfin_transfer_ops_u16 = {
+	.write  = bfin_sport_spi_u16_writer,
+	.read   = bfin_sport_spi_u16_reader,
+	.duplex = bfin_sport_spi_u16_duplex,
+};
+
+/* stop controller and re-config current chip*/
+static void
+bfin_sport_spi_restore_state(struct bfin_sport_spi_master_data *drv_data)
+{
+	struct bfin_sport_spi_slave_data *chip = drv_data->cur_chip;
+	unsigned int bits = (drv_data->ops == &bfin_transfer_ops_u8 ? 7 : 15);
+
+	bfin_sport_spi_disable(drv_data);
+	dev_dbg(drv_data->dev, "restoring spi ctl state\n");
+
+	bfin_write(&drv_data->regs->tcr1, chip->ctl_reg);
+	bfin_write(&drv_data->regs->tcr2, bits);
+	bfin_write(&drv_data->regs->tclkdiv, chip->baud);
+	bfin_write(&drv_data->regs->tfsdiv, bits);
+	SSYNC();
+
+	bfin_write(&drv_data->regs->rcr1, chip->ctl_reg & ~(ITCLK | ITFS));
+	bfin_write(&drv_data->regs->rcr2, bits);
+	SSYNC();
+
+	bfin_sport_spi_cs_active(chip);
+}
+
+/* test if there is more transfer to be done */
+static enum bfin_sport_spi_state
+bfin_sport_spi_next_transfer(struct bfin_sport_spi_master_data *drv_data)
+{
+	struct spi_message *msg = drv_data->cur_msg;
+	struct spi_transfer *trans = drv_data->cur_transfer;
+
+	/* Move to next transfer */
+	if (trans->transfer_list.next != &msg->transfers) {
+		drv_data->cur_transfer =
+		    list_entry(trans->transfer_list.next,
+			       struct spi_transfer, transfer_list);
+		return RUNNING_STATE;
+	} else
+		return DONE_STATE;
+}
+
+/*
+ * caller already set message->status;
+ * dma and pio irqs are blocked give finished message back
+ */
+static void
+bfin_sport_spi_giveback(struct bfin_sport_spi_master_data *drv_data)
+{
+	struct bfin_sport_spi_slave_data *chip = drv_data->cur_chip;
+	unsigned long flags;
+	struct spi_message *msg;
+
+	spin_lock_irqsave(&drv_data->lock, flags);
+	msg = drv_data->cur_msg;
+	drv_data->state = START_STATE;
+	drv_data->cur_msg = NULL;
+	drv_data->cur_transfer = NULL;
+	drv_data->cur_chip = NULL;
+	queue_work(drv_data->workqueue, &drv_data->pump_messages);
+	spin_unlock_irqrestore(&drv_data->lock, flags);
+
+	if (!drv_data->cs_change)
+		bfin_sport_spi_cs_deactive(chip);
+
+	if (msg->complete)
+		msg->complete(msg->context);
+}
+
+static irqreturn_t
+sport_err_handler(int irq, void *dev_id)
+{
+	struct bfin_sport_spi_master_data *drv_data = dev_id;
+	u16 status;
+
+	dev_dbg(drv_data->dev, "%s enter\n", __func__);
+	status = bfin_read(&drv_data->regs->stat) & (TOVF | TUVF | ROVF | RUVF);
+
+	if (status) {
+		bfin_write(&drv_data->regs->stat, status);
+		SSYNC();
+
+		bfin_sport_spi_disable(drv_data);
+		dev_err(drv_data->dev, "status error:%s%s%s%s\n",
+			status & TOVF ? " TOVF" : "",
+			status & TUVF ? " TUVF" : "",
+			status & ROVF ? " ROVF" : "",
+			status & RUVF ? " RUVF" : "");
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void
+bfin_sport_spi_pump_transfers(unsigned long data)
+{
+	struct bfin_sport_spi_master_data *drv_data = (void *)data;
+	struct spi_message *message = NULL;
+	struct spi_transfer *transfer = NULL;
+	struct spi_transfer *previous = NULL;
+	struct bfin_sport_spi_slave_data *chip = NULL;
+	unsigned int bits_per_word;
+	u32 tranf_success = 1;
+	u8 full_duplex = 0;
+
+	/* Get current state information */
+	message = drv_data->cur_msg;
+	transfer = drv_data->cur_transfer;
+	chip = drv_data->cur_chip;
+
+	if (transfer->speed_hz)
+		bfin_write(&drv_data->regs->tclkdiv, hz_to_spi_baud(transfer->speed_hz));
+	else
+		bfin_write(&drv_data->regs->tclkdiv, chip->baud);
+	SSYNC();
+
+	/*
+	 * if msg is error or done, report it back using complete() callback
+	 */
+
+	 /* Handle for abort */
+	if (drv_data->state == ERROR_STATE) {
+		dev_dbg(drv_data->dev, "transfer: we've hit an error\n");
+		message->status = -EIO;
+		bfin_sport_spi_giveback(drv_data);
+		return;
+	}
+
+	/* Handle end of message */
+	if (drv_data->state == DONE_STATE) {
+		dev_dbg(drv_data->dev, "transfer: all done!\n");
+		message->status = 0;
+		bfin_sport_spi_giveback(drv_data);
+		return;
+	}
+
+	/* Delay if requested at end of transfer */
+	if (drv_data->state == RUNNING_STATE) {
+		dev_dbg(drv_data->dev, "transfer: still running ...\n");
+		previous = list_entry(transfer->transfer_list.prev,
+				      struct spi_transfer, transfer_list);
+		if (previous->delay_usecs)
+			udelay(previous->delay_usecs);
+	}
+
+	if (transfer->len == 0) {
+		/* Move to next transfer of this msg */
+		drv_data->state = bfin_sport_spi_next_transfer(drv_data);
+		/* Schedule next transfer tasklet */
+		tasklet_schedule(&drv_data->pump_transfers);
+	}
+
+	if (transfer->tx_buf != NULL) {
+		drv_data->tx = (void *)transfer->tx_buf;
+		drv_data->tx_end = drv_data->tx + transfer->len;
+		dev_dbg(drv_data->dev, "tx_buf is %p, tx_end is %p\n",
+			transfer->tx_buf, drv_data->tx_end);
+	} else
+		drv_data->tx = NULL;
+
+	if (transfer->rx_buf != NULL) {
+		full_duplex = transfer->tx_buf != NULL;
+		drv_data->rx = transfer->rx_buf;
+		drv_data->rx_end = drv_data->rx + transfer->len;
+		dev_dbg(drv_data->dev, "rx_buf is %p, rx_end is %p\n",
+			transfer->rx_buf, drv_data->rx_end);
+	} else
+		drv_data->rx = NULL;
+
+	drv_data->cs_change = transfer->cs_change;
+
+	/* Bits per word setup */
+	bits_per_word = transfer->bits_per_word ? : message->spi->bits_per_word;
+	if (bits_per_word == 8)
+		drv_data->ops = &bfin_transfer_ops_u8;
+	else
+		drv_data->ops = &bfin_transfer_ops_u16;
+
+	drv_data->state = RUNNING_STATE;
+
+	if (drv_data->cs_change)
+		bfin_sport_spi_cs_active(chip);
+
+	dev_dbg(drv_data->dev,
+		"now pumping a transfer: width is %d, len is %d\n",
+		bits_per_word, transfer->len);
+
+	/* PIO mode write then read */
+	dev_dbg(drv_data->dev, "doing IO transfer\n");
+
+	bfin_sport_spi_enable(drv_data);
+	if (full_duplex) {
+		/* full duplex mode */
+		BUG_ON((drv_data->tx_end - drv_data->tx) !=
+		       (drv_data->rx_end - drv_data->rx));
+		drv_data->ops->duplex(drv_data);
+
+		if (drv_data->tx != drv_data->tx_end)
+			tranf_success = 0;
+	} else if (drv_data->tx != NULL) {
+		/* write only half duplex */
+
+		drv_data->ops->write(drv_data);
+
+		if (drv_data->tx != drv_data->tx_end)
+			tranf_success = 0;
+	} else if (drv_data->rx != NULL) {
+		/* read only half duplex */
+
+		drv_data->ops->read(drv_data);
+		if (drv_data->rx != drv_data->rx_end)
+			tranf_success = 0;
+	}
+	bfin_sport_spi_disable(drv_data);
+
+	if (!tranf_success) {
+		dev_dbg(drv_data->dev, "IO write error!\n");
+		drv_data->state = ERROR_STATE;
+	} else {
+		/* Update total byte transfered */
+		message->actual_length += transfer->len;
+		/* Move to next transfer of this msg */
+		drv_data->state = bfin_sport_spi_next_transfer(drv_data);
+		if (drv_data->cs_change)
+			bfin_sport_spi_cs_deactive(chip);
+	}
+
+	/* Schedule next transfer tasklet */
+	tasklet_schedule(&drv_data->pump_transfers);
+}
+
+/* pop a msg from queue and kick off real transfer */
+static void
+bfin_sport_spi_pump_messages(struct work_struct *work)
+{
+	struct bfin_sport_spi_master_data *drv_data;
+	unsigned long flags;
+	struct spi_message *next_msg;
+
+	drv_data = container_of(work, struct bfin_sport_spi_master_data, pump_messages);
+
+	/* Lock queue and check for queue work */
+	spin_lock_irqsave(&drv_data->lock, flags);
+	if (list_empty(&drv_data->queue) || !drv_data->run) {
+		/* pumper kicked off but no work to do */
+		drv_data->busy = 0;
+		spin_unlock_irqrestore(&drv_data->lock, flags);
+		return;
+	}
+
+	/* Make sure we are not already running a message */
+	if (drv_data->cur_msg) {
+		spin_unlock_irqrestore(&drv_data->lock, flags);
+		return;
+	}
+
+	/* Extract head of queue */
+	next_msg = list_entry(drv_data->queue.next,
+		struct spi_message, queue);
+
+	drv_data->cur_msg = next_msg;
+
+	/* Setup the SSP using the per chip configuration */
+	drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
+
+	list_del_init(&drv_data->cur_msg->queue);
+
+	/* Initial message state */
+	drv_data->cur_msg->state = START_STATE;
+	drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
+					    struct spi_transfer, transfer_list);
+	bfin_sport_spi_restore_state(drv_data);
+	dev_dbg(drv_data->dev, "got a message to pump, "
+		"state is set to: baud %d, cs_gpio %i, ctl 0x%x\n",
+		drv_data->cur_chip->baud, drv_data->cur_chip->cs_gpio,
+		drv_data->cur_chip->ctl_reg);
+
+	dev_dbg(drv_data->dev,
+		"the first transfer len is %d\n",
+		drv_data->cur_transfer->len);
+
+	/* Mark as busy and launch transfers */
+	tasklet_schedule(&drv_data->pump_transfers);
+
+	drv_data->busy = 1;
+	spin_unlock_irqrestore(&drv_data->lock, flags);
+}
+
+/*
+ * got a msg to transfer, queue it in drv_data->queue.
+ * And kick off message pumper
+ */
+static int
+bfin_sport_spi_transfer(struct spi_device *spi, struct spi_message *msg)
+{
+	struct bfin_sport_spi_master_data *drv_data = spi_master_get_devdata(spi->master);
+	unsigned long flags;
+
+	spin_lock_irqsave(&drv_data->lock, flags);
+
+	if (!drv_data->run) {
+		spin_unlock_irqrestore(&drv_data->lock, flags);
+		return -ESHUTDOWN;
+	}
+
+	msg->actual_length = 0;
+	msg->status = -EINPROGRESS;
+	msg->state = START_STATE;
+
+	dev_dbg(&spi->dev, "adding an msg in transfer()\n");
+	list_add_tail(&msg->queue, &drv_data->queue);
+
+	if (drv_data->run && !drv_data->busy)
+		queue_work(drv_data->workqueue, &drv_data->pump_messages);
+
+	spin_unlock_irqrestore(&drv_data->lock, flags);
+
+	return 0;
+}
+
+/* Called every time common spi devices change state */
+static int
+bfin_sport_spi_setup(struct spi_device *spi)
+{
+	struct bfin_sport_spi_slave_data *chip, *first = NULL;
+	int ret;
+
+	/* Only alloc (or use chip_info) on first setup */
+	chip = spi_get_ctldata(spi);
+	if (chip == NULL) {
+		struct bfin5xx_spi_chip *chip_info;
+
+		chip = first = kzalloc(sizeof(*chip), GFP_KERNEL);
+		if (!chip)
+			return -ENOMEM;
+
+		/* platform chip_info isn't required */
+		chip_info = spi->controller_data;
+		if (chip_info) {
+			/*
+			 * DITFS and TDTYPE are only thing we don't set, but
+			 * they probably shouldn't be changed by people.
+			 */
+			if (chip_info->ctl_reg || chip_info->enable_dma) {
+				ret = -EINVAL;
+				dev_err(&spi->dev, "don't set ctl_reg/enable_dma fields");
+				goto error;
+			}
+			chip->cs_chg_udelay = chip_info->cs_chg_udelay;
+			chip->idle_tx_val = chip_info->idle_tx_val;
+			spi->bits_per_word = chip_info->bits_per_word;
+		}
+	}
+
+	if (spi->bits_per_word != 8 && spi->bits_per_word != 16) {
+		ret = -EINVAL;
+		goto error;
+	}
+
+	/* translate common spi framework into our register
+	 * following configure contents are same for tx and rx.
+	 */
+
+	if (spi->mode & SPI_CPHA)
+		chip->ctl_reg &= ~TCKFE;
+	else
+		chip->ctl_reg |= TCKFE;
+
+	if (spi->mode & SPI_LSB_FIRST)
+		chip->ctl_reg |= TLSBIT;
+	else
+		chip->ctl_reg &= ~TLSBIT;
+
+	/* Sport in master mode */
+	chip->ctl_reg |= ITCLK | ITFS | TFSR | LATFS | LTFS;
+
+	chip->baud = hz_to_spi_baud(spi->max_speed_hz);
+
+	chip->cs_gpio = spi->chip_select;
+	ret = gpio_request(chip->cs_gpio, spi->modalias);
+	if (ret)
+		goto error;
+
+	dev_dbg(&spi->dev, "setup spi chip %s, width is %d\n",
+			spi->modalias, spi->bits_per_word);
+	dev_dbg(&spi->dev, "ctl_reg is 0x%x, GPIO is %i\n",
+			chip->ctl_reg, spi->chip_select);
+
+	spi_set_ctldata(spi, chip);
+
+	bfin_sport_spi_cs_deactive(chip);
+
+	return ret;
+
+ error:
+	kfree(first);
+	return ret;
+}
+
+/*
+ * callback for spi framework.
+ * clean driver specific data
+ */
+static void
+bfin_sport_spi_cleanup(struct spi_device *spi)
+{
+	struct bfin_sport_spi_slave_data *chip = spi_get_ctldata(spi);
+
+	if (!chip)
+		return;
+
+	gpio_free(chip->cs_gpio);
+
+	kfree(chip);
+}
+
+static int
+bfin_sport_spi_init_queue(struct bfin_sport_spi_master_data *drv_data)
+{
+	INIT_LIST_HEAD(&drv_data->queue);
+	spin_lock_init(&drv_data->lock);
+
+	drv_data->run = false;
+	drv_data->busy = 0;
+
+	/* init transfer tasklet */
+	tasklet_init(&drv_data->pump_transfers,
+		     bfin_sport_spi_pump_transfers, (unsigned long)drv_data);
+
+	/* init messages workqueue */
+	INIT_WORK(&drv_data->pump_messages, bfin_sport_spi_pump_messages);
+	drv_data->workqueue =
+	    create_singlethread_workqueue(dev_name(drv_data->master->dev.parent));
+	if (drv_data->workqueue == NULL)
+		return -EBUSY;
+
+	return 0;
+}
+
+static int
+bfin_sport_spi_start_queue(struct bfin_sport_spi_master_data *drv_data)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&drv_data->lock, flags);
+
+	if (drv_data->run || drv_data->busy) {
+		spin_unlock_irqrestore(&drv_data->lock, flags);
+		return -EBUSY;
+	}
+
+	drv_data->run = true;
+	drv_data->cur_msg = NULL;
+	drv_data->cur_transfer = NULL;
+	drv_data->cur_chip = NULL;
+	spin_unlock_irqrestore(&drv_data->lock, flags);
+
+	queue_work(drv_data->workqueue, &drv_data->pump_messages);
+
+	return 0;
+}
+
+static inline int
+bfin_sport_spi_stop_queue(struct bfin_sport_spi_master_data *drv_data)
+{
+	unsigned long flags;
+	unsigned limit = 500;
+	int status = 0;
+
+	spin_lock_irqsave(&drv_data->lock, flags);
+
+	/*
+	 * This is a bit lame, but is optimized for the common execution path.
+	 * A wait_queue on the drv_data->busy could be used, but then the common
+	 * execution path (pump_messages) would be required to call wake_up or
+	 * friends on every SPI message. Do this instead
+	 */
+	drv_data->run = false;
+	while (!list_empty(&drv_data->queue) && drv_data->busy && limit--) {
+		spin_unlock_irqrestore(&drv_data->lock, flags);
+		msleep(10);
+		spin_lock_irqsave(&drv_data->lock, flags);
+	}
+
+	if (!list_empty(&drv_data->queue) || drv_data->busy)
+		status = -EBUSY;
+
+	spin_unlock_irqrestore(&drv_data->lock, flags);
+
+	return status;
+}
+
+static inline int
+bfin_sport_spi_destroy_queue(struct bfin_sport_spi_master_data *drv_data)
+{
+	int status;
+
+	status = bfin_sport_spi_stop_queue(drv_data);
+	if (status)
+		return status;
+
+	destroy_workqueue(drv_data->workqueue);
+
+	return 0;
+}
+
+static int __devinit
+bfin_sport_spi_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct bfin5xx_spi_master *platform_info;
+	struct spi_master *master;
+	struct resource *res, *ires;
+	struct bfin_sport_spi_master_data *drv_data;
+	int status;
+
+	platform_info = dev->platform_data;
+
+	/* Allocate master with space for drv_data */
+	master = spi_alloc_master(dev, sizeof(*master) + 16);
+	if (!master) {
+		dev_err(dev, "cannot alloc spi_master\n");
+		return -ENOMEM;
+	}
+
+	drv_data = spi_master_get_devdata(master);
+	drv_data->master = master;
+	drv_data->dev = dev;
+	drv_data->pin_req = platform_info->pin_req;
+
+	master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
+	master->bus_num = pdev->id;
+	master->num_chipselect = platform_info->num_chipselect;
+	master->cleanup = bfin_sport_spi_cleanup;
+	master->setup = bfin_sport_spi_setup;
+	master->transfer = bfin_sport_spi_transfer;
+
+	/* Find and map our resources */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res == NULL) {
+		dev_err(dev, "cannot get IORESOURCE_MEM\n");
+		status = -ENOENT;
+		goto out_error_get_res;
+	}
+
+	drv_data->regs = ioremap(res->start, resource_size(res));
+	if (drv_data->regs == NULL) {
+		dev_err(dev, "cannot map registers\n");
+		status = -ENXIO;
+		goto out_error_ioremap;
+	}
+
+	ires = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!ires) {
+		dev_err(dev, "cannot get IORESOURCE_IRQ\n");
+		status = -ENODEV;
+		goto out_error_get_ires;
+	}
+	drv_data->err_irq = ires->start;
+
+	/* Initial and start queue */
+	status = bfin_sport_spi_init_queue(drv_data);
+	if (status) {
+		dev_err(dev, "problem initializing queue\n");
+		goto out_error_queue_alloc;
+	}
+
+	status = bfin_sport_spi_start_queue(drv_data);
+	if (status) {
+		dev_err(dev, "problem starting queue\n");
+		goto out_error_queue_alloc;
+	}
+
+	status = request_irq(drv_data->err_irq, sport_err_handler,
+		0, "sport_spi_err", drv_data);
+	if (status) {
+		dev_err(dev, "unable to request sport err irq\n");
+		goto out_error_irq;
+	}
+
+	status = peripheral_request_list(drv_data->pin_req, DRV_NAME);
+	if (status) {
+		dev_err(dev, "requesting peripherals failed\n");
+		goto out_error_peripheral;
+	}
+
+	/* Register with the SPI framework */
+	platform_set_drvdata(pdev, drv_data);
+	status = spi_register_master(master);
+	if (status) {
+		dev_err(dev, "problem registering spi master\n");
+		goto out_error_master;
+	}
+
+	dev_info(dev, "%s, regs_base@%p\n", DRV_DESC, drv_data->regs);
+	return 0;
+
+ out_error_master:
+	peripheral_free_list(drv_data->pin_req);
+ out_error_peripheral:
+	free_irq(drv_data->err_irq, drv_data);
+ out_error_irq:
+ out_error_queue_alloc:
+	bfin_sport_spi_destroy_queue(drv_data);
+ out_error_get_ires:
+	iounmap(drv_data->regs);
+ out_error_ioremap:
+ out_error_get_res:
+	spi_master_put(master);
+
+	return status;
+}
+
+/* stop hardware and remove the driver */
+static int __devexit
+bfin_sport_spi_remove(struct platform_device *pdev)
+{
+	struct bfin_sport_spi_master_data *drv_data = platform_get_drvdata(pdev);
+	int status = 0;
+
+	if (!drv_data)
+		return 0;
+
+	/* Remove the queue */
+	status = bfin_sport_spi_destroy_queue(drv_data);
+	if (status)
+		return status;
+
+	/* Disable the SSP at the peripheral and SOC level */
+	bfin_sport_spi_disable(drv_data);
+
+	/* Disconnect from the SPI framework */
+	spi_unregister_master(drv_data->master);
+
+	peripheral_free_list(drv_data->pin_req);
+
+	/* Prevent double remove */
+	platform_set_drvdata(pdev, NULL);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int
+bfin_sport_spi_suspend(struct platform_device *pdev, pm_message_t state)
+{
+	struct bfin_sport_spi_master_data *drv_data = platform_get_drvdata(pdev);
+	int status;
+
+	status = bfin_sport_spi_stop_queue(drv_data);
+	if (status)
+		return status;
+
+	/* stop hardware */
+	bfin_sport_spi_disable(drv_data);
+
+	return status;
+}
+
+static int
+bfin_sport_spi_resume(struct platform_device *pdev)
+{
+	struct bfin_sport_spi_master_data *drv_data = platform_get_drvdata(pdev);
+	int status;
+
+	/* Enable the SPI interface */
+	bfin_sport_spi_enable(drv_data);
+
+	/* Start the queue running */
+	status = bfin_sport_spi_start_queue(drv_data);
+	if (status)
+		dev_err(drv_data->dev, "problem resuming queue\n");
+
+	return status;
+}
+#else
+# define bfin_sport_spi_suspend NULL
+# define bfin_sport_spi_resume  NULL
+#endif
+
+static struct platform_driver bfin_sport_spi_driver = {
+	.driver	= {
+		.name = DRV_NAME,
+	},
+	.probe   = bfin_sport_spi_probe,
+	.remove  = __devexit_p(bfin_sport_spi_remove),
+	.suspend = bfin_sport_spi_suspend,
+	.resume  = bfin_sport_spi_resume,
+};
+
+static int __init bfin_sport_spi_init(void)
+{
+	return platform_driver_register(&bfin_sport_spi_driver);
+}
+module_init(bfin_sport_spi_init);
+
+static void __exit bfin_sport_spi_exit(void)
+{
+	platform_driver_unregister(&bfin_sport_spi_driver);
+}
+module_exit(bfin_sport_spi_exit);